[0/3] T-ROM2.5.$Z (CORRECTION!)

[...]
RM> But it is not recommended to access port #CFF7 programmatically. Or rather
RM> you can climb, but
RM> it may turn out to be inaccessible - these are user mikriki.
^^^^^^^^^^^^^^^^^^^^^^^^^^^
Correction: this is putting it mildly!
Port #CFF7 is not programmatically accessible. And it is controlled from the SetUp menu "MADROM".

All the best.
Sincerely, Roman.